- PanaXseries_ MICROCOMPUTER MN102H MN102H75K/F75K/85K/F85K LSI User's Manual
MN102HF75K Flash EEPROM Version
Using the Onboard Serial Programming Mode
MN102H75K/F75K/85K/F85K LSI User Manual Panasonic Semiconductor Development Company
321
Panasonic
B.4.2 Circuit Requirements for the Target Board
■ During programming, the serial writer supplies V
PP
 to the microcontroller. 
Install a switch on the target board to toggle between V
PP
 supplied by the 
serial writer and V
PP
 for normal operation.
■ In serial programing a large-scale of current flows through Vpp. See to it that 
5V is supplied to Vpp by checking the connection and reducing the 
impedance of switches.
■ You must supply a V
DD
 source of 3.0 V – 3.3 V externally.
■ V
DD
 (for level detection) informs the serial writer of the actual V
DD
 level of 
the target board. If the V
DD
 level is too low, the serial writer generates an 
error message.
■ Connect pullup resistors on the target board to the RST
, SBT, and SBD pins. 
Use a pullup resistor value of 10 kΩ ±10%. Install a switch on the target 
board to toggle between RST
 for serial programming and RST for normal 
operation. Alternatively, install a wired-OR connection. For a wired-OR 
connection, disable RST
 for normal operation during serial programming.
■ RST
, SBT, and SBD are output from the serial writer through an open con-
nection.
Figure B-6 Target Board–Serial Writer Connection
Table B-3 Pin Descriptions for Target Board–Serial Writer Connection
Pin Name Description
V
PP
5-V power supply
V
DD
3.0–3.3 external power supply
V
DD
 (for level detection) V
DD
 level detection pin for target board
RST
Reset
SBT Serial interface clock supply
SBD Serial interface data supply
GND Ground
Note: 1. During normal microcontroller operation, V
PP
 should always be equal to 
V
DD
 (3.3 ±0.3 V). Apply 5 V to the V
PP
 supply only when programming 
the flash memory.
Serial
writer
V
PP
 = +5 V
GND
SBT
SBD
RST
V
DD
 (for level detection)
MCU
SBT1
SBD1
RST
V
PP
External
power sourc
e
3.0 V - 3.3 V
V
DD
GND
10 k
Ω
Target board










